1. Field of the Invention
This invention relates to a stage apparatus for moving and positioning an object highly accurately which is suitable for various measuring apparatuses and a projection exposure apparatus or the like used in a semiconductor lithography process, and an exposure apparatus such as a step and repeat exposure apparatus and a device producing method using the same.
2. Related Background Art
FIG. 10 of the accompanying drawings shows an example of the construction of a stage apparatus according to the conventional art. In FIG. 10, the reference numeral 51 designates a stage base on which is placed a Y stage 52 as a moving mechanism in Y direction. The reference numeral 53 denotes a DC servo motor for converting rotative motion into linear motion by a ball screw and driving the Y stage 52, and the DC servo motor 53 is fixed to the stage base 51. The reference numeral 54 designates an X stage placed on the Y stage 52, and the reference numeral 55 denotes a DC servo motor for converting rotative motion into linear motion by a ball screw 56 and driving the X stage 54, and the DC servo motor 55 is fixed to the Y stage 52. The reference numeral 1 designates a table for holding the stage base 51. The reference characters 9a and 9b denote reflecting mirrors for a laser length measuring machine, and the reflecting mirrors 9a and 9b are fixed to the X stage 54. The reference character 8a designates the interferometer of the laser length measuring machine for detecting the position of the X stage 54 in X direction, and the interferometer 8a is fixed to the table 1 with a mounting stand 10 interposed therebetween. The reference numeral 13 denotes mount members for interrupting the transmission of vibration from a floor on which the apparatus is installed.
In the above-described construction, when the Y stage 52 and the X stage 54 are driven, the reaction force of an inertia force resulting from the acceleration and deceleration of a movable body is transmitted to the table 1. However, there has been the problem that when the support reaction force resulting from the acceleration and deceleration of the movable body is transmitted to the table 1, the natural vibration of a mechanism system supported by the mount members 13 is excited and disturbance vibration is transmitted to the X stage 54, the Y stage 52 and the laser interferometer 8a to thereby hamper rapid and highly accurate feeding.